Cement



106. comrosinows.

COATING OR PLASTIC.

nwt WK ".To all whom it may concern:

Be it known that I, VERNER FREDERIK LAssoE SMIDTH, engineer, a subject of the King of Denmark, residing in Copenhagen, in

the Kingdom of Denmark, have invented certain new and useful Improvements in Cement, called Sand-Cement, of which the fol lowing is a specification.

The object of this invention is to convert .re the different kinds of cement in the market, mainly' however, Portland cement, into a new kind of cement by which a mortar is obtained that has all the good properties of cementmorta'r but is just as cheap if not cheaper than r 5 the ordinarylime-mortar. The ordinary cem- ,cnt-mortar is obtained by mixing one part of cement with from one to four parts of sand: sometimes even astill greater quantity of sand is used. When the quantity of sand in proportion to the quantity of cementisincreased too much, it is impossible to obtain the requi red intimate mixture of the substances. At the same time the resistance of the mortar is diminished, and the cement prevented from acting as a suflicient acting medicine for all sary when the mortar is to harden into asolid mass.

The object of this inyention is therefore to grind the ordinary cement of commerce,suoh as Portland-cement Roman-cement &c., with a certain q'uantity of tliesamefillmg material which is employed for making mortar, namely, s and (or) ravel and produce thereb f a mix- 55 "t'ure called sand-cement: an e invention .cousists of a cement, composed of a ground mixture of Portland or Roman cement, and sand or gravel, as will be fully described here- 'J'naf er and finally pointed out in the claim. In preparing the sand-cement, a dry mixture of one part of cement is ground with say three parts of sand,'so that four parts of sand- 3 ementis obtained. This sand-cement is then i used in the same manner as ordinary cement I twe ii wae h tw (tracer UNITED STATES V FREDERIK LASSOE SMIDTH, OF COPENHAGEN, DENMARK.-

o' 1 ge'a v L CEMENT. A 6 1 a y k i kw 1 4 SPECIFICATION forming part of Letters Patent No. 494,763, dated April 4, 1893.

' Application filed July 19, 1892. Serial No. 440,554. (No specimens.)

the grains of sand, which is absolutely neces- PATENT OFFICE.

. by mixing one part of the same with one or more parts of the filling material (sand, gravel, &c.),so that from one part of cement, say four parts of sand cement and from the latter six teen parts by weight of mortar are obtained The said cement-mortar thus obtained has the following advantages:

First. For filling up the interstices betwee the grains of sand there is used not only the more expensive cement, but also the cheaper finely ground sand-filler.

Second. In grinding the cement with the filling material, this substances areyitxed very intimately together. In making mortar, the cement is everywhere pres 561 in finely com minuted state, provided that not more sand is used in the mixture with the sand-cement, that the interstices between the grains of sand are fully and completely filled thereby.

Third. In grinding the cementtogether with the filling material the cement is obtained as c in a finer condition than before so that it can cover a larger surface thanbefore, and consequently bind together a greater number of grains of sand.

It may be added that a series of practical tests made with sand-cement, demonstrated clearly that by the same a mortar of comparatively high binding capacity is obtained.

Having thus described my invention, I claim as new and desire to secure by Letters Patent The improved cement herein described, consisting of a dry ground mixture of ordinary cement and sand, gravel or other filling material, substantially as set forth. "wes'titnony that I claim the foregoing as my invention I haye signed my name in presence of two subscribing witnesses. V

TERNER FREDERIK LASSOE SMIDTH.

Witnesses:

HARALD LARsEN, HANS FR. BoJn. 

